名词解释题维生素(vitamin)
题目
名词解释题
维生素(vitamin)
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更多“维生素(vitamin)”相关问题
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第1题：
there is no reason that they should limit how much vitamin you take ____ they can limit how much water you drink.A. any more than
B. no more than
C. much more than
D. no less than
参考答案：A
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第2题：
Vitamin C helps to combat stress either from worry or from intense _____ exercise.()A. handicapped
B. physical
C. limited
D. maximum
参考答案：B
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第3题：
共用题干
Which foods should be eaten to keep us healthy?Let us look at some important vitamins for these answers.
Vitamin A helps prevent skin and other tissues from becoming dry.People who do not get enough vitamin A cannot see well in darkness.Vitamin A is found in fish liver oil.It also is in the yellow part of eggs.Sweet potatoes,carrots and other darkly colored fruits and vegetables contain substances that the body can change into vitamin A.
Vitamin B-one changes starchy（含淀粉的）foods into energy. It also helps the heart and nervous system work smoothly.Without it,we would be weak and would not grow.Vitamin B-one is found not just in whole grains like brown rice,but also in other foods.These include beans and peas,nuts,and meat and fish.
Vitamin B-twelve is needed so folic acid（叶酸）can do its work. Together, they help produce red blood cells.Vitamin B-twelve is found naturally in foods such as eggs,meat,fish and milk products.Folic acid has been shown to prevent physical problems in babies when taken by their mothers during pregnancy.Vitamin B-twelve is found in green leafy vegetables and other foods,like legumes and citrus fruits.In some countries,it is added to products like bread.
Vitamin C is needed for strong bones and teeth,and for healthy blood passages.It also helps wounds heal quickly.The body stores little vitamin C.So we must get it every day in foods such as citrus（柑橘类）fruits,tomatoes and uncooked cabbage.
Vitamin D increases levels of the element calcium in the blood.Calcium is needed for nerve and muscle cells to work normally.It also is needed to build strong bones.Ultraviolet light from the sun changes a substance in the skin into vitamin D.Fish liver oil also contains vitamin D.
Vitamin K is needed for healthy blood.It thickens the blood around a cut to stop bleeding. Vitamin K can be found in pork products,liver and in vegetables like cabbage,kale and spinach.In most countries,vitamin B-twelve is added to products like bread.
A:Right
B:Wrong
C:Not mentioned答案：B解析：第二段第四句说，蛋黄也含有维生素A。因此选A。
第三段最后两句说，维生素B，不仅存在于全谷类食品，如糙米，还存在于其他的食物里，包括豆类、坚果、肉类和鱼类。因此选B。
第四段最后一句："In some countries, it is added to products like bread.”在一些国家，它被添加到面包等产品中，而不是in most countries。因此选B。
第五段最后一句说，所以我们必须每天食用柑橘类水果、西红柿和生卷心菜以摄取维生素C。因此选A。
第二段第三句说，鱼肝油富含维生素A。第六段最后一句说，鱼肝油也含有维生素D。因此选D。
最后一段说，健康的血液需要维生素K。它通过增加创口周围的血液私稠度来止血。猪肉产品、肝脏和蔬菜（像卷心菜、甘蓝和菠菜）富含维生素K。因此选B。
维生素有助于人体健康，但文章并没有提到维生素越多越好，因此选择C。 -
第4题：
共用题干
Daisy Williams admits genes play some role in the way she looks,but believes diet is an important factor."It doesn't matter how good the genes are if you don't eat properly and take care of your-self,"she says."If you want to look good,get plenty of rest,exercise every day,eat mostly raw fruits and vegetables and quit worrying."
Nowhere do the signs of aging manifest themselves more clearly than in the condition of the skin. When your weight fluctuates（波动）,the skin stretches with each up cycle , but it may not completely shrink back to its original size in the down cycle. As a result,the skin may sag（松弛下垂）.
Zinc and vitamin A are important for normal,healthy skin.Zinc helps the skin repair itself, and vitamin A aids in keeping skin supple,preventing dryness and helping shed dead cells.Good sources of zinc are beef,eggs and seafood,while many dark-green leafy vegetables are rich in beta carotene（胡萝卜素）, which the body converts to vitamin A.
Vitamin C helps improve the blood supply to the skin and aids in forming collagen（胶原）. Good sources of vitamin C include citrus fruits and juices,cauliflower,snow peas,red and green peppers,broccoli,white and sweet potatoes, tomatoes,watermelon,and honeydew melon.
How food is prepared matters too.The longer vegetables cook,the greater the loss of vitamins. Don't soak vegetables when washing them,since water-soluble vitamins such as C will be lost.
Good general nutrition is essential to maintaining a healthy,youthful appearance.And the key to good general nutrition is balance.Proteins should make up roughly 10 percent of your daily calorie intake;no more than 30 percent should come from fats;and the remaining calories should come mostly from complex carbohydrates（碳水化合物）.Dark-green leafy vegetables are good sources of beta carotene.
A:Right
B:Wrong
C:Not mentioned答案：A解析：文章第一句说，黛西?威廉斯承认基因对她的相貌有一定的影响，但她认为饮食是一个重要因素。因此选项A是正确的。
文章第二段说，体重波动会导致皮肤松弛，而不是题目中所说的体重增加，因此该句不正确。
答案相关句在第三段最后一句："Good sources of zinc are beef, eggs and seafood...（锌的主要来源是牛肉、鸡蛋和海鲜······）"，而不是维生素A的，因此选B。
答案相关句在第三段最后："...while many dark-green leafy vegetables are rich in beta carotene, which the body converts to vitamin A.”因此该句正确。
答案相关句在第五段第二句：" The longer vegetables cook , the greater the loss of vitamins.”因此选B。
根据常识，该句似乎是正确的，但文章中并没有提到“In order to look younger, one should cut back on fats.”因此选C。
文章的主题是保持年轻皮肤的关键是营养平衡，而不是题中说的如何减肥。因此选择B。 -
第5题：
共用题干
Daisy Williams admits genes play some role in the way she looks,but believes diet is an important factor."It doesn't matter how good the genes are if you don't eat properly and take care of your-self,"she says."If you want to look good,get plenty of rest,exercise every day,eat mostly raw fruits and vegetables and quit worrying."
Nowhere do the signs of aging manifest themselves more clearly than in the condition of the skin. When your weight fluctuates（波动）,the skin stretches with each up cycle , but it may not completely shrink back to its original size in the down cycle. As a result,the skin may sag（松弛下垂）.
Zinc and vitamin A are important for normal,healthy skin.Zinc helps the skin repair itself, and vitamin A aids in keeping skin supple,preventing dryness and helping shed dead cells.Good sources of zinc are beef,eggs and seafood,while many dark-green leafy vegetables are rich in beta carotene（胡萝卜素）, which the body converts to vitamin A.
Vitamin C helps improve the blood supply to the skin and aids in forming collagen（胶原）. Good sources of vitamin C include citrus fruits and juices,cauliflower,snow peas,red and green peppers,broccoli,white and sweet potatoes, tomatoes,watermelon,and honeydew melon.
How food is prepared matters too.The longer vegetables cook,the greater the loss of vitamins. Don't soak vegetables when washing them,since water-soluble vitamins such as C will be lost.
Good general nutrition is essential to maintaining a healthy,youthful appearance.And the key to good general nutrition is balance.Proteins should make up roughly 10 percent of your daily calorie intake;no more than 30 percent should come from fats;and the remaining calories should come mostly from complex carbohydrates（碳水化合物）.The longer vegetables cook,the greater vitamin C remains.
A:Right
B:Wrong
C:Not mentioned答案：B解析：文章第一句说，黛西?威廉斯承认基因对她的相貌有一定的影响，但她认为饮食是一个重要因素。因此选项A是正确的。
文章第二段说，体重波动会导致皮肤松弛，而不是题目中所说的体重增加，因此该句不正确。
答案相关句在第三段最后一句："Good sources of zinc are beef, eggs and seafood...（锌的主要来源是牛肉、鸡蛋和海鲜······）"，而不是维生素A的，因此选B。
答案相关句在第三段最后："...while many dark-green leafy vegetables are rich in beta carotene, which the body converts to vitamin A.”因此该句正确。
答案相关句在第五段第二句：" The longer vegetables cook , the greater the loss of vitamins.”因此选B。
根据常识，该句似乎是正确的，但文章中并没有提到“In order to look younger, one should cut back on fats.”因此选C。
文章的主题是保持年轻皮肤的关键是营养平衡，而不是题中说的如何减肥。因此选择B。 -
第6题：
Vitamins are similar because they are made of the same elements—usually carbon,hydrogen,oxygen,and sometimes nitrogen.They are different in that their elements are arranged differently,and each vitamin been（ ）one or more specific functions in the body.A.holds
B.plays
C.performs答案：A解析：根据句意，所选项要有“起作用”的含义。四个选项中，只有D.perform“执行，履行”与function相搭配，意为“起作用”。A.undertake“着手，承担”；B.hold“抓住，掌握”；C.play常和part或role搭配，也可表达“起作用”之意。 -
第7题：
共用题干
Food and Cancer
Medical experts have suspected for many years that there is a strong link between what a person eats and
cancer. They say a new study provides the first evidence that vitamins could reduce a person's chance of
developing cancer. A team of Chinese and American scientists did the study.They are from American
National Cancer Institute and the Cancer Institute of the Chinese Academy of Medical Sciences in Beijing.
The Journal of the National Cancer Institute published the results of the study. About thirty thousand people
between the ages of 40 to 69 took part in the study.They were from the northern central Chinese area of
Linxian.Most of them took vitamins and minerals everyday for five years.
Linxian was chosen because the people there have an extremely high rate of cancer of stomach and
esophagus.Researchers believe that fungus and molds in local foods may be partly responsible for the high
cancer rate.Researchers divided those people into eight groups.Seven of the groups received different
mixtures of vitamins and minerals daily.The amounts of the vitamins and minerals were 1 to 2 times greater
than what American health officials say is needed.The eighth group received sugar pills that had no effect.
Those who seemed to gain the most received a mixture of a form of vitamin A called β-carotene,vitamin E
and the mineral selenium（硒）.The vitamin and mineral are believed to prevent damage to cells caused by
cancer-causing substances.Researchers reported a 1 3 percent drop in cancer rates in those who took
β-carotene,vitamin E and selenium.They also found a 10 percent drop in the number of deaths caused by
strokes from bursting blood vessels.
Scientists warn that it is too soon to know if the effect would be the same among people in other
countries.They note that the people in Linxian eat foods that lack necessary vitamins and minerals.Chinese
officials will continue to record the health records of the people in Linxian for many years.For now officials
reportedly are considering using the results of the study.They want to find a way to improve the health of
people in Linxian and other small towns in China.The rate of cancer of stomach and esophagus in Linxian is the highest in China.
A:Right
B:Wrong
C:Not mentioned答案：C解析：文章第一段第一句“Medical Experts have suspected for many years that there is a strong link between what a person eats and cancer.They say a new study provides the first evidence that vi- tamins could reduce a person ' s chance of developing cancer.”意思是“医学专家很多年来一直怀 疑人们的饮食和癌症之间有直接的联系，他们（医学专家）一项新的研究提供了第一个证 据······”，因此可见新的研究结果不是意料之外，而是意料之中的。
文中说来自中美两家研究所的科学家们共同进行了此项研究，并没有提及具体人数。 故C为正确答案。
由文章第一段最后一句“Most of them took vitamins and minerals everyday for five years." 可知，大多数实验对象连续5年每天服用各种维生素及矿物质，因此可推知，实验大约持续了5 年。故A为正确答案。
文章第二段的开头说林县人胃癌及食道癌发病率极高，但并没有说在国内是最高的。 故C为正确答案。
文章第二段中提到，研究者认为，此地食物中的真菌和霉菌是癌症发病率高的一个原 因。故A为正确答案。
文章第二段中提到，研究者把实验对象分成8组，其中的7组每天服用不同的维生素和 矿物质混合物，第8组服用毫无作用的糖丸。故B为正确答案。
文章最后一段第一句“Scientists warn that it is too soon to know if the effect would be the same among people in other countries."，意思说“目前太早了还不能知道是否这个影响对其他 国家的人们是一样”；最后一句“They want to find a way to improved the health of people in Linx- ian and other small towns in China."，在最后一句中提到仍然是宁夏和中国的其他小城市的问 题。因此判断问题干句的说法不正确。第3部分：概括大意与完成句子 -
第8题：
There is no reason they should limit how much vitamin you take，( )they can limit how much water you drink.A.much more than
B.no more than
C.no less than
D.any more than答案：D解析：考查比较结构。A项意为“比...多得多”；B项意为“和……一样不，仅仅”；C项意为“多达”；D项no...more than意为“两者都不”，其强调形式为not...any more than。由于前一句已有否定词no，因此D项正确。故本题选D。句意：正如他们无权限制人们喝多少水一样，他们也没有理由限制人们摄入多少维生素。 -
第9题：
脂肪能够促进（）等维生素的吸收。
- A、维生素A、维生素D、维生素K
- B、维生素B、维生素C、维生素E
- C、维生素C、维生素K、维生素U
- D、维生素PP、维生素A、维生素E。
正确答案:A -
第10题：
哪一个药在Medicare保险计划中没有被完全禁止报销？（）
- A、Viagra 25 mg
- B、Vitamin B-12 500 mcg
- C、Sildenafil 20 mg
- D、以上均不是
正确答案:C -
第11题：
单选题Donna thinks that ______ can help Mary think more clearly.Aeating a lot of sugar
Bstudying six hours every day
Cdrinking a lot of coffee
Deating foods high in Vitamin B
正确答案： A解析：
由“建议3”可知选项 D正确。 -
第12题：
问答题Passage 1 IF VITAMIN C is good for you, does more mean better? Millions of people think so but scientists have been divided on the issue. Despite a huge research effort, there is little evidence that megadoses of vitamin C, up to 100 times the recommended daily amounts, have beneficial effects. Now an American scientist has come up with an explanation of the lack of effect—and a simple remedy. Millions of Americans take supplements of the vitamin in the belief that its anti-oxidant properties help prevent heart disease, cancer and the ageing process. Most of it, however, goes straight down the pan: the body cannot deal with excess vitamin C, which is rapidly excreted. Even large doses are eliminated in 12 hours and slow-release ones in 16. The way to keep blood levels of the vitamin continuously high, according to Roc Ordman, Professor of Biochemistry at Beloit College, Wisconsin, is to take it twice a day—one 500 milligram does every 12 hours. “If vitamin C really does work as an antioxidant, then taking a supplement once a day might be like wearing a condom half the time.” Professor Ordman said. “Nobody has ever thought to look at how much you have to take to keep the level elevated.” In a study published in the current issue of the gerontology journal Age, Professor Ordman gave varying doses of vitamin C at different times to students and measured the amount excreted in their urine. He found a 500 mg dose was needed every 12 hours “to enrich the blood just enough to ensure there is a little bit leaking out all the time.” This compares with the US-recommended adult daily allowance of 60 mgs. Recommended levels of vitamin C, and other vitamins, have been raised following recognition of their role in mopping up “free radicals” in the blood linked with a range of diseases. However, the British figure of 40 mgs daily for vitamin C is still below the U.S. figure and likely to be raised again. Research on megadoses of vitamin C of 10 and 20 times this level have shown it to have some protective effect against the common cold taken at the first sign. But there is no evidence of a beneficial effect against other diseases of doses vastly higher than the recommended daily amounts. LINUS PAULING, the Nobel Laureate, whose book on vitamin C and the common cold in 1970 popularised the idea of taking fistfuls of supplements, is said to have swallowed 10,000 mgs a day. It is because it is water-soluble and quickly excreted that vitamin C is safe in such quantities; it does not build up in the tissues. Professor Ordman’s twice-daily regime may help keep blood levels of the vitamin high. But dosing on the scale followed by Pauling, who died last August aged 93, will seriously damage your bank balance—at $ 2,500 a year. 1. What do you know about Professor Ordman’s view towards vitamin C from the passage? 2. Why was the Nobel Prize winner Linus Pauling mentioned in the passage? 3. Explain in your town words the sentence from paragraph 2 “Most of it, however, goes straight down the pan”. 4. What is concluded about effects of megadoses of vitamin C in the passage?正确答案： 【参考答案】
1. Professor Ordman found that taking vitamin C twice a day (one 500mg dose every 12 hours) can keep blood levels of the vitamin continuously high. He was not definte/certain about vitamin C’s anti-oxidant properties.
2. Because Pauling’s book on vitamin C popularized the idea of taking large doses of vitamin C. He is also known for taking huge doses/megadoses of vitamin C every day.
3. The sentence can be paraphrased as: However, most of the vitamin taken becomes/is useless//has no effects//brings no obvious effects.
4. Megadoses of vitamin C have some protective effect against the common cold. However there is no evidence of a beneficial effect against other diseases (such as heart disease, cancer and ageing process.)解析： 暂无解析 -
第13题：
The doctor told me I had to expect such things at my age and simply _____ some vitamin pills.()A. dissolved
B. stuffed
C. recommended
D. prescribed
参考答案：D
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第14题：
下列何者为非化妆品中禁用之成分?
A.hexachlorophene
B.vitamin A acid
C.methylene chloride
D.zinc oxide
正确答案：D
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第15题：
共用题干
Which foods should be eaten to keep us healthy?Let us look at some important vitamins for these answers.
Vitamin A helps prevent skin and other tissues from becoming dry.People who do not get enough vitamin A cannot see well in darkness.Vitamin A is found in fish liver oil.It also is in the yellow part of eggs.Sweet potatoes,carrots and other darkly colored fruits and vegetables contain substances that the body can change into vitamin A.
Vitamin B-one changes starchy（含淀粉的）foods into energy. It also helps the heart and nervous system work smoothly.Without it,we would be weak and would not grow.Vitamin B-one is found not just in whole grains like brown rice,but also in other foods.These include beans and peas,nuts,and meat and fish.
Vitamin B-twelve is needed so folic acid（叶酸）can do its work. Together, they help produce red blood cells.Vitamin B-twelve is found naturally in foods such as eggs,meat,fish and milk products.Folic acid has been shown to prevent physical problems in babies when taken by their mothers during pregnancy.Vitamin B-twelve is found in green leafy vegetables and other foods,like legumes and citrus fruits.In some countries,it is added to products like bread.
Vitamin C is needed for strong bones and teeth,and for healthy blood passages.It also helps wounds heal quickly.The body stores little vitamin C.So we must get it every day in foods such as citrus（柑橘类）fruits,tomatoes and uncooked cabbage.
Vitamin D increases levels of the element calcium in the blood.Calcium is needed for nerve and muscle cells to work normally.It also is needed to build strong bones.Ultraviolet light from the sun changes a substance in the skin into vitamin D.Fish liver oil also contains vitamin D.
Vitamin K is needed for healthy blood.It thickens the blood around a cut to stop bleeding. Vitamin K can be found in pork products,liver and in vegetables like cabbage,kale and spinach.The more Vitamins we have,the more healthy we will be.
A:Right
B:Wrong
C:Not mentioned答案：C解析：第二段第四句说，蛋黄也含有维生素A。因此选A。
第三段最后两句说，维生素B，不仅存在于全谷类食品，如糙米，还存在于其他的食物里，包括豆类、坚果、肉类和鱼类。因此选B。
第四段最后一句："In some countries, it is added to products like bread.”在一些国家，它被添加到面包等产品中，而不是in most countries。因此选B。
第五段最后一句说，所以我们必须每天食用柑橘类水果、西红柿和生卷心菜以摄取维生素C。因此选A。
第二段第三句说，鱼肝油富含维生素A。第六段最后一句说，鱼肝油也含有维生素D。因此选D。
最后一段说，健康的血液需要维生素K。它通过增加创口周围的血液私稠度来止血。猪肉产品、肝脏和蔬菜（像卷心菜、甘蓝和菠菜）富含维生素K。因此选B。
维生素有助于人体健康，但文章并没有提到维生素越多越好，因此选择C。 -
第16题：
共用题干
Daisy Williams admits genes play some role in the way she looks,but believes diet is an important factor."It doesn't matter how good the genes are if you don't eat properly and take care of your-self,"she says."If you want to look good,get plenty of rest,exercise every day,eat mostly raw fruits and vegetables and quit worrying."
Nowhere do the signs of aging manifest themselves more clearly than in the condition of the skin. When your weight fluctuates（波动）,the skin stretches with each up cycle , but it may not completely shrink back to its original size in the down cycle. As a result,the skin may sag（松弛下垂）.
Zinc and vitamin A are important for normal,healthy skin.Zinc helps the skin repair itself, and vitamin A aids in keeping skin supple,preventing dryness and helping shed dead cells.Good sources of zinc are beef,eggs and seafood,while many dark-green leafy vegetables are rich in beta carotene（胡萝卜素）, which the body converts to vitamin A.
Vitamin C helps improve the blood supply to the skin and aids in forming collagen（胶原）. Good sources of vitamin C include citrus fruits and juices,cauliflower,snow peas,red and green peppers,broccoli,white and sweet potatoes, tomatoes,watermelon,and honeydew melon.
How food is prepared matters too.The longer vegetables cook,the greater the loss of vitamins. Don't soak vegetables when washing them,since water-soluble vitamins such as C will be lost.
Good general nutrition is essential to maintaining a healthy,youthful appearance.And the key to good general nutrition is balance.Proteins should make up roughly 10 percent of your daily calorie intake;no more than 30 percent should come from fats;and the remaining calories should come mostly from complex carbohydrates（碳水化合物）.Both genes and diets affects people's look.
A:Right
B:Wrong
C:Not mentioned答案：A解析：文章第一句说，黛西?威廉斯承认基因对她的相貌有一定的影响，但她认为饮食是一个重要因素。因此选项A是正确的。
文章第二段说，体重波动会导致皮肤松弛，而不是题目中所说的体重增加，因此该句不正确。
答案相关句在第三段最后一句："Good sources of zinc are beef, eggs and seafood...（锌的主要来源是牛肉、鸡蛋和海鲜······）"，而不是维生素A的，因此选B。
答案相关句在第三段最后："...while many dark-green leafy vegetables are rich in beta carotene, which the body converts to vitamin A.”因此该句正确。
答案相关句在第五段第二句：" The longer vegetables cook , the greater the loss of vitamins.”因此选B。
根据常识，该句似乎是正确的，但文章中并没有提到“In order to look younger, one should cut back on fats.”因此选C。
文章的主题是保持年轻皮肤的关键是营养平衡，而不是题中说的如何减肥。因此选择B。 -
第17题：
共用题干
Which foods should be eaten to keep us healthy?Let us look at some important vitamins for these answers.
Vitamin A helps prevent skin and other tissues from becoming dry.People who do not get enough vitamin A cannot see well in darkness.Vitamin A is found in fish liver oil.It also is in the yellow part of eggs.Sweet potatoes,carrots and other darkly colored fruits and vegetables contain substances that the body can change into vitamin A.
Vitamin B-one changes starchy（含淀粉的）foods into energy. It also helps the heart and nervous system work smoothly.Without it,we would be weak and would not grow.Vitamin B-one is found not just in whole grains like brown rice,but also in other foods.These include beans and peas,nuts,and meat and fish.
Vitamin B-twelve is needed so folic acid（叶酸）can do its work. Together, they help produce red blood cells.Vitamin B-twelve is found naturally in foods such as eggs,meat,fish and milk products.Folic acid has been shown to prevent physical problems in babies when taken by their mothers during pregnancy.Vitamin B-twelve is found in green leafy vegetables and other foods,like legumes and citrus fruits.In some countries,it is added to products like bread.
Vitamin C is needed for strong bones and teeth,and for healthy blood passages.It also helps wounds heal quickly.The body stores little vitamin C.So we must get it every day in foods such as citrus（柑橘类）fruits,tomatoes and uncooked cabbage.
Vitamin D increases levels of the element calcium in the blood.Calcium is needed for nerve and muscle cells to work normally.It also is needed to build strong bones.Ultraviolet light from the sun changes a substance in the skin into vitamin D.Fish liver oil also contains vitamin D.
Vitamin K is needed for healthy blood.It thickens the blood around a cut to stop bleeding. Vitamin K can be found in pork products,liver and in vegetables like cabbage,kale and spinach.Fish liver oil contains vitamin A and vitamin D.
A:Right
B:Wrong
C:Not mentioned答案：A解析：第二段第四句说，蛋黄也含有维生素A。因此选A。
第三段最后两句说，维生素B，不仅存在于全谷类食品，如糙米，还存在于其他的食物里，包括豆类、坚果、肉类和鱼类。因此选B。
第四段最后一句："In some countries, it is added to products like bread.”在一些国家，它被添加到面包等产品中，而不是in most countries。因此选B。
第五段最后一句说，所以我们必须每天食用柑橘类水果、西红柿和生卷心菜以摄取维生素C。因此选A。
第二段第三句说，鱼肝油富含维生素A。第六段最后一句说，鱼肝油也含有维生素D。因此选D。
最后一段说，健康的血液需要维生素K。它通过增加创口周围的血液私稠度来止血。猪肉产品、肝脏和蔬菜（像卷心菜、甘蓝和菠菜）富含维生素K。因此选B。
维生素有助于人体健康，但文章并没有提到维生素越多越好，因此选择C。 -
第18题：
Getting enough vitamins is essential to life,although the body has no nutritional use for（ ）vitamins.Many people,nevertheless,believe in being on the“safe side”and thus take extra vitamins.However,a well‐balanced diet will usually meet all the body's vitamin needs.A.exceptional
B.exceeding
C.excess
D.external答案：C解析：excess“额外的，超额的，多余的”，并与下文中的extra相呼应。第一句意为：“虽然多余的维生素对身体没有营养作用，但吸收足够的维生素对生命至关重要。”A.exceptional“不寻常的，例外的”；B.exceeding“超越的，非常的”；D.external“外部的，外面的”。 -
第19题：
共用题干
Food and Cancer
Medical experts have suspected for many years that there is a strong link between what a person eats and
cancer. They say a new study provides the first evidence that vitamins could reduce a person's chance of
developing cancer. A team of Chinese and American scientists did the study.They are from American
National Cancer Institute and the Cancer Institute of the Chinese Academy of Medical Sciences in Beijing.
The Journal of the National Cancer Institute published the results of the study. About thirty thousand people
between the ages of 40 to 69 took part in the study.They were from the northern central Chinese area of
Linxian.Most of them took vitamins and minerals everyday for five years.
Linxian was chosen because the people there have an extremely high rate of cancer of stomach and
esophagus.Researchers believe that fungus and molds in local foods may be partly responsible for the high
cancer rate.Researchers divided those people into eight groups.Seven of the groups received different
mixtures of vitamins and minerals daily.The amounts of the vitamins and minerals were 1 to 2 times greater
than what American health officials say is needed.The eighth group received sugar pills that had no effect.
Those who seemed to gain the most received a mixture of a form of vitamin A called β-carotene,vitamin E
and the mineral selenium（硒）.The vitamin and mineral are believed to prevent damage to cells caused by
cancer-causing substances.Researchers reported a 1 3 percent drop in cancer rates in those who took
β-carotene,vitamin E and selenium.They also found a 10 percent drop in the number of deaths caused by
strokes from bursting blood vessels.
Scientists warn that it is too soon to know if the effect would be the same among people in other
countries.They note that the people in Linxian eat foods that lack necessary vitamins and minerals.Chinese
officials will continue to record the health records of the people in Linxian for many years.For now officials
reportedly are considering using the results of the study.They want to find a way to improve the health of
people in Linxian and other small towns in China.All those people who took part in the study received vitamins and minerals.
A:Right
B:Wrong
C:Not mentioned答案：B解析：文章第一段第一句“Medical Experts have suspected for many years that there is a strong link between what a person eats and cancer.They say a new study provides the first evidence that vi- tamins could reduce a person ' s chance of developing cancer.”意思是“医学专家很多年来一直怀 疑人们的饮食和癌症之间有直接的联系，他们（医学专家）一项新的研究提供了第一个证 据······”，因此可见新的研究结果不是意料之外，而是意料之中的。
文中说来自中美两家研究所的科学家们共同进行了此项研究，并没有提及具体人数。 故C为正确答案。
由文章第一段最后一句“Most of them took vitamins and minerals everyday for five years." 可知，大多数实验对象连续5年每天服用各种维生素及矿物质，因此可推知，实验大约持续了5 年。故A为正确答案。
文章第二段的开头说林县人胃癌及食道癌发病率极高，但并没有说在国内是最高的。 故C为正确答案。
文章第二段中提到，研究者认为，此地食物中的真菌和霉菌是癌症发病率高的一个原 因。故A为正确答案。
文章第二段中提到，研究者把实验对象分成8组，其中的7组每天服用不同的维生素和 矿物质混合物，第8组服用毫无作用的糖丸。故B为正确答案。
文章最后一段第一句“Scientists warn that it is too soon to know if the effect would be the same among people in other countries."，意思说“目前太早了还不能知道是否这个影响对其他 国家的人们是一样”；最后一句“They want to find a way to improved the health of people in Linx- ian and other small towns in China."，在最后一句中提到仍然是宁夏和中国的其他小城市的问 题。因此判断问题干句的说法不正确。第3部分：概括大意与完成句子 -
第20题：
维生素主要有（）等多种
- A、维生素A、维生素B1、维生素B2、维生素C、维生素D
- B、维生素H、维生素A1、维生素A2、维生素D1、维生素F
- C、C、维生素维生素F1、维生素A2、维生素D1、维生素F
- D、D、维生素E、维生素维生素G、维生素H、维生素F
正确答案:A -
第21题：
维生素(vitamin)
正确答案:是一类动物本身不能合成但对动物生长和健康又是必需的有机化合物，所以必须从饮食中获得。许多辅酶都是由维生素衍生的。 -
第22题：
下列有关维生素A的叙述哪些是正确的（）
- A、环外的4个双键必须与环内双键共轭
- B、增加环内双键的数目，活性增加
- C、双键被饱和，活性下降
- D、增加环内双键的数目，活性下降
- E、遇lewis酸可发生脱水反应，生成脱水vitamin A活性下降
正确答案:A,C,D,E -
第23题：
多选题下列有关维生素A的叙述哪些是正确的（）A环外的4个双键必须与环内双键共轭
B增加环内双键的数目，活性增加
C双键被饱和，活性下降
D增加环内双键的数目，活性下降
E遇lewis酸可发生脱水反应，生成脱水vitamin A活性下降
正确答案： C,B解析： 暂无解析